Lornoxicam & Tenoxicam Drugs as Green Corrosion Inhibitors for Carbon Steel in 1 M H<sub>2</sub>SO<sub>4</sub> Solution

Fouda, A.S.; El-Defrawy, A.M.; El-Sherbeni, M.W.

doi:2013.4.2.47

J. Electrochem. Sci. Technol > Volume 4(2); 2013 > Article

Article

Journal of Electrochemical Science and Technology 2013;4(2):47-56.
DOI: https://doi.org/10.5229/JECST.2013.4.2.47

Lornoxicam & Tenoxicam Drugs as Green Corrosion Inhibitors for Carbon Steel in 1 M H₂SO₄ Solution

A.S. Fouda, A.M. El-Defrawy, M.W. El-Sherbeni

Department of Chemistry, Faculty of Science, El-Mansoura University;Department of Chemistry, Faculty of Science, El-Mansoura University;Department of Chemistry, Faculty of Science, El-Mansoura University;

Abstract

Inhibition performance of Lornoxicam & Tenoxicam against corrosion of carbon steel in 1M $H_2SO_4$ solutions was investigated by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements. The inhibition efficiency increased with increasing inhibitor's concentration, but decreased with increase in temperature. Potentiodynamic polarization curves showed that, the inhibitors were of mixed type. The apparent activation energy ($E^*_a$) and other thermodynamic parameters for the corrosion process have also been calculated and discussed. The inhibition of carbon steel corrosion is due to the adsorption of the inhibitor molecules on the surface, which follows Temkin adsorption isotherm. The mechanism of inhibition was discussed in the light of the chemical structure of the undertaken inhibitors.

Key Words: Acid corrosion, Carbon steel, EIS, Polarization